1. Field of the Invention
The present invention relates to a power supply and a program for feeding power to virtual host computers each running a virtual machine in emulation, the virtual machine controlled by a virtualization management server.
2. Description of the Related Art
Virtualization management is generally used for effective utilization of the resources of physical computers. The virtualization management uses the physical computers as virtual hosts. Each virtual host is configured to run one or multiple virtual machines (VMs) in emulation. In the virtualization management, a VM is sometimes migrated to a different virtual host depending upon the running situations of the VMs. Using a structure that allows flexible migration of a VM to any virtual host makes it possible to effectively utilize the resources of the physical computers.
Meanwhile, there are methods that use a power control device to reduce the power consumption of the physical computers (see Japanese Patent Application Publication No. 2008-269249, for example). In the method described in Japanese Patent Application Publication No. 2008-269249, the power control device collects the load statuses of systems, migrates a system to a given physical computer on the basis of the load statuses, and turns off the power of the unselected physical computer. By causing the power control device to perform both virtualization management and power management as described above, the power consumption of the physical computers can be expected to be reduced.
However, the method described in Japanese Patent Application Publication No. 2008-269249 has a problem that the power control device becomes unable to perform not only the power management but also the virtualization management if there is a power fault in the power supply feeding power to the power control device.
In view of such a circumstance, a power supply configured to perform virtualization management of VMs and power management of the VMs and their virtual hosts has been proposed (see Japanese Patent Application Publication No. 2012-038157). According to the method described in Japanese Patent Application Publication No. 2012-038157, the power supply manages so as to perform the virtualization management and the power feed in conjunction with each other in accordance with preset schedule data. Thus, the system can be operated stably.
Moreover, there is a configuration using POWERCHUTE™ Network Shutdown (PCNS) or the like in a general virtual system for the purpose of power control (see IBM Japan, Ltd. “IBM UPS Management in VMware ESX/ESXi 4.x Environment”, Page 5 “What is POWERCHUTE™ Network Shutdown (PCNS)?”, [online], 2011, IBM Japan, Ltd., [searched May 17, 2012], and an IBM document obtained from the Internet (hereinafter, Non-patent Document), for example). When power feed to an UPS is stopped due to a power failure, computers fed with power from this UPS must be shut down while the battery of the UPS feeds power. Thus, in the method described in Non-patent Document, when power feed to an UPS is stopped due to a power failure, the power supply notifies a PCNS on the service console of a virtual system that the power feed has been stopped. Then, to start a shutdown, a virtual host computer shuts down the guest OS of each VM. Once the shutdown of the guest OS is complete, the virtual host computer shuts down. Such a PCNS is installed and executed on a VM in some cases.